Horizontal support member for tube and clamp scaffold assembly

ABSTRACT

A horizontal support member is provided for use with tube and clamp scaffold systems. The support member includes a bar, preferably a length of scaffold tubing, having a tube half-clamp welded to each end. Attaching each tube half-clamp of the support member to a vertical scaffold tube will result in the support member becoming horizontal. Attaching a plurality of support members of the same fixed length between adjacent vertical scaffold tubes as transoms and ledgers maintains a uniform distance between the vertical scaffold tubes and provides a scaffold system that is quick to assemble. A tube half-clamp including a base with scaffold brace fastening means projecting perpendicular from the base is also provided. Attaching tube half-clamps with brace fastening means to a tube and clamp scaffold assembly permits the use of conventional scaffold braces, such as lengths of metal tubes with flattened ends or angle iron and having apertures at each end, as diagonal braces to stabilize the assembled scaffold.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is concerned with horizontal support members for tube and clamp scaffold systems.

2. Description of the Prior Art

Scaffold systems are temporary structures typically constructed to provide safe access to a building or structure during the construction phase of the building or structure or when major service is required. A scaffold system provides a safe work platform for workers once assembled.

One of the most common scaffold systems are tube and clamp systems. FIG. 1 illustrates an example of a prior art tube and clamp scaffold system. Tube and clamp scaffold systems typically consist of vertical metal tubes releasably fastened to horizontal metal tubes through the use of releasable clamps that join the vertical and horizontal tubes together. The clamps used to join a horizontal or diagonal tube to a vertical tube is usually a two-part swivel clamp. This clamp consists of two opposing clamshell-style half-clamps having bases that are joined together with a swivel joint. Each half-clamp clamps onto a single tube. Two half-clamps may also be permanently affixed to one another in a right angle configuration to form a right-angle clamp for specifically joining horizontal tubes to vertical tubes. FIGS. 2A and 2B illustrate two types of prior art scaffold tube clamps. FIG. 2C illustrates a prior art swivel clamp that permits one part of the clamp to fasten to a vertical tube whereas the other part can swivel to accommodate a horizontal support tube or a diagonal brace tube.

A section of scaffold would have four vertical tubes, one at each corner of the section. Horizontal tubes are placed around the perimeter of the section both near the bottom and near the top of the vertical tubes in an overlapping fashion to maintain the section in a rectangular configuration. The horizontal tubes are referred to as either “transoms” or “ledgers” depending on where they are positioned on the scaffold structure. Transoms are used to support planks or walkways for workers to walk along the scaffold structure whereas ledgers are placed between vertical tubes in parallel with the planks or walkways to support the structure itself. A diagonal brace is used to ensure the rigidity of the scaffold section by extending from a high elevation on one vertical tube to a low elevation on an adjacent vertical tube.

Sections of scaffold can be stacked one on top of another by using insert pins that fit into the ends of the vertical tubes such that the lower end of an upper section couples to the upper end of the lower vertical tube, thereby permitting the scaffold to be built up in height. On the ground level scaffold section, the lower ends of the vertical tubes are coupled to base plates to stabilize the scaffold structure. On uneven ground surfaces, leveling jacks may be placed at the bottom of one or all of the vertical tubes to adjust for the uneven ground height and maintain the scaffold section in a vertical orientation. All of the foregoing is well known to those skilled in the art.

The problem with this form of scaffold system is that it requires two clamping operations to be performed at each joining of a horizontal or diagonal brace to a vertical tube, one for each of the vertical and horizontal or diagonal tubes. Furthermore, when it is desirable to keep the scaffold sections rectangular, additional time and effort is required to ensure that each horizontal tube along a side of the scaffold section is clamped at the same distance apart between the vertical tubes so that they remain vertical. This adds additional time required to assemble the scaffold and additional expense for the number of clamps that are required.

Another disadvantage of this type of scaffold is that the use of metal tubes as diagonal braces. Tubes of varying length are required to span the diagonal distances between vertical tubes. Other forms of scaffolding systems, as are well known to those skilled in the art, use braces either of angle iron or metal tubes with flattened ends having holes at each end to receive pins affixed to a scaffold section. These pins are usually equipped with quick release locking mechanisms that permit a brace to be quickly and easily attached to and removed from the scaffold section with minimal effort.

It is, therefore, desirable to have a tube and clamp scaffold system having horizontal support members using fewer clamping connections so that the scaffold system can be assembled in less time and maintain uniform distance between the vertical tubes on any given side of a scaffold section. It is also desirable to have a diagonal brace clamp for a vertical tube that can receive conventional braces made of angle iron.

SUMMARY OF THE INVENTION

The present invention is concerned with a tube and clamp scaffold system using conventional vertical metal scaffold tubes and horizontal support members of predetermined fixed lengths. Each support horizontal support member is a rigid bar, preferably a metal scaffold tube, having first and second ends defining a longitudinal axis.

Each horizontal support member has a half-clamp attached to each of its two ends. preferably, the half-clamps are welded to the support member. Each half-clamp is adapted to clamp a vertical tube. The two half-clamps of the horizontal support member are oriented in the same direction such that once the horizontal support member is fastened to two adjacent vertical tubes, the support member is horizontal and perpendicular to the vertical tubes. In attaching a number of horizontal support members of predetermined fixed lengths between adjacent vertical tubes as transoms and ledgers, the vertical tubes are maintained at a uniform, predetermined fixed distance apart along their height. By providing such a horizontal support member, only one clamping operation is required at each joining of a horizontal support member to a vertical tube instead of two. This reduces the time required to assemble the scaffold system. In addition, by using predetermined fixed lengths of horizontal support members, there is no need to measure each horizontal tube from mounting between adjacent vertical tubes as the length of the support member is already fixed. Yet another benefit is that the number of half-clamps required to assemble a scaffold is cut in half thereby reducing the cost of assembling the structure.

Another aspect of the present invention includes a half-clamp having fastening means, such as a bolt and nut or a quick release locking mechanism or brace pin, for use with conventional scaffold braces as are well known to those skilled in the art. Conventional braces include lengths of angle iron or metal tubes with flattened ends. Each end of a scaffold brace comprises an aperture for receiving a fastener for attaching to a scaffold structure. When assembling the scaffold system of the present invention, a brace clamp can be placed at any point on one vertical tube and a second brace clamp can be placed at the appropriate point on an adjacent vertical tube for attaching a diagonal brace of a fixed length. The fastening means of the brace clamps extend through the apertures of the scaffold brace for releasably securing the brace to the brace clamp thereby adding rigidity to the scaffold structure.

Broadly stated, one aspect of the present invention is a support member for a tube and clamp scaffold system comprising a rigid bar having first and second ends and defining a longitudinal axis, and a half-clamp at each of the first and second ends, each half-clamp oriented to clamp a tube whose axis is substantially perpendicular to said longitudinal axis, the half-clamps oriented in substantially the same direction whereupon attaching each half-clamp of the rigid bar to a substantially vertical scaffold tube causes the support member to be substantially horizontal.

Broadly stated, another aspect of the present invention is a scaffold system comprising a plurality of substantially vertical scaffold tubes positioned in a spaced-apart configuration, and a plurality of substantially horizontal support members releasably connected to each pair of adjacent vertical scaffold tubes, each support member comprising a rigid bar having first and second ends and defining a longitudinal axis, the bar having a half-clamp at each of the first and second ends, each half-clamp oriented to clamp a tube whose axis is substantially perpendicular to said longitudinal axis, the half-clamps oriented in substantially the same direction whereupon attaching each half-clamp of a support member to a substantially vertical scaffold tube causes said support member to be substantially horizontal.

Broadly stated, another aspect of the present invention is a brace clamp for a scaffold brace having first and second ends, each end having an aperture for receiving a fastener, comprising a half-clamp having a base, and a fastener for releasably attaching a scaffold brace to the support clamp, the fastener projecting substantially perpendicular from the base of the support clamp and the support clamp being attached to a scaffold tube having a longitudinal axis, the fastener extending substantially perpendicular to the longitudinal axis for attaching to an aperture of the scaffold brace.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a prior art tube and clamp scaffold system.

FIGS. 2A, 2B and 2C are perspective views of prior art clamshell swivel tube clamps.

FIG. 3 is a perspective view of a horizontal support member of the present invention.

FIG. 4 is a side elevational view of a horizontal support member of the present invention.

FIG. 5 is a perspective view of one tube clamp of a horizontal support member of the present invention.

FIG. 6 is a perspective view of a scaffold system of the present invention.

FIG. 7A is a perspective view of one embodiment of the brace clamp of the present invention.

FIG. 7B is a perspective view of an alternate embodiment of the brace clamp of the present invention.

FIG. 8 is a perspective view of a scaffold system of the present invention equipped with a diagonal brace.

FIG. 9 is a perspective view of a scaffold system of the present invention equipped with a scissors brace.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is concerned with a horizontal support member for use with a tube and clamp scaffold system. The horizontal support member consists of a rigid bar and a clamshell half-clamp attached to each end of the bar. Typically, the clamps may include models P1001, P2001 and P1146 made by van Thiel United b.v. of the Netherlands and model SW 2×2 made by Etobicoke Ironworks Limited of Weston, Ontario, Canada. Those skilled in the art will understand that any acceptable style of tube half-clamp for use with tube and clamp scaffold systems may be used with the present invention.

Referring to FIGS. 3, 4 and 5, support member 10 consists of rigid bar 12 having a half-clamp 14 welded at each end of bar 12. In the preferred embodiment, bar 12 is a length of Schedule 40 steel scaffold tubing having an inside diameter of 1.5 inches or an outside diameter of 1.9 inches. Half-clamp 14 is attached, preferably welded, to each end of bar 12. Each half-clamp 14 is attached such that it will clamp a tube that is perpendicular to the longitudinal axis of bar 12. Both half-clamps 14 on a bar 12 are oriented in the same direction such that when support member 10 is attached to two adjacent vertical tubes 16, support member 10 is substantially horizontal.

Referring to FIG. 6, scaffold system 15 consists of a plurality of vertical tubes 16 in a spaced-apart configuration. In the first course, or ground-level section, of scaffold system 15, the bottom of each vertical tube 16 may have a base plate 18 or a leveling jack 20. Leveling jack 20 allows for adjustment in height of vertical tube 16 to compensate for variations in ground elevation where scaffold system 15 is located. Support members 10 are attached to adjacent pairs of vertical tubes 16. Typically, a section of scaffold system 15 is rectangular in cross-section with support members 10 placed at positions both low and high along the height of vertical tube 16 to stabilize the structure of scaffold system 15 and to maintain uniform distance between vertical tubes 16. To accommodate scaffold structures of varying sizes, support members 10 may be provided in various fixed lengths.

In the preferred embodiment of the present invention, two support members 10 act as transoms 11 whereas two support members 10 act as ledgers 13. Transoms 11 support planks or walkways 17 whereas ledgers 13 provide support for scaffold system 15 itself.

Scaffold system 15 may be built up in height by stacking vertical tubes 16 one on top of another. Insert pins 19 are placed between adjoining sections of vertical tubes 16 to connect them together. Additional support members 10 are then placed between adjacent pairs of vertical tubes 16 of the upper section.

Further stabilization of scaffold system 15 is accomplished by placing diagonal braces between selected pairs of adjacent vertical tubes 16. As shown in FIGS. 8 and 9, brace clamps 22 are attached to an adjacent pair of vertical tubes 16 that brace 28 will attach to. Brace 28 may consist of a piece of angle-iron or a metal tube with its ends flattened. At each end of brace 28 are apertures 29. Brace clamp 22 consists of a half-clamp 14 attached to base 24, preferably welded together. Extending perpendicular from base 24 is brace fastener 26. As shown in FIGS. 7A and 7B, brace fastener 26 may be a bolt and nut or it may consist of a releasable mechanism to receive and capture an end of brace 28 via aperture 29. Those skilled in the art will understand that any acceptable style of brace attachment mechanism may be used. As brace 28 is used as a diagonal brace, one brace clamp 22 is placed at a low elevation on one vertical tube 16 while another brace clamp 22 is placed at a higher elevation on the adjacent vertical tube 16. The distance between brace fasteners 26 is the same as the distance between apertures 29 on brace 28.

In another embodiment, brace clamp 22 may be used with a scissors-type brace 30 which has two braces 28 attached by a swivel joint 31 mid-way along their length. The use of this type of brace requires the use of four brace clamps 22, two on each adjacent vertical tubes 16.

Although a few preferred embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications might be made without departing from the scope of the invention. The terms and expressions in the preceding specification have been used therein as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding equivalents of the features shown and described or portions thereof, it being recognized that the scope of the invention is defined and limited only by the claims that follow. 

1. A support member for a tube and clamp scaffold system, comprising: a rigid bar having first and second ends and defining a longitudinal axis; and a half-clamp at each of the first and second ends, each half-clamp oriented to clamp a tube whose axis is substantially perpendicular to the longitudinal axis of the rigid bar, the half-clamps oriented in substantially the same direction whereupon attaching each half-clamp of the rigid bar to a substantially vertical scaffold tube causes the support member to be substantially horizontal.
 2. The support member as set forth in claim 1 wherein the bar is a metal scaffold tube.
 3. The support member as set forth in claim 1 wherein the half-clamps are welded to the bar.
 4. The support member as set forth in claim 1 wherein each half-clamp is a releasable clamshell clamp.
 5. A support member for a tube and clamp scaffold system, comprising: a metal scaffold tube having first and second ends and defining a longitudinal axis; and a releasable clamshell half-clamp welded to each of the first and second ends, each half-clamp oriented to clamp a tube whose axis is substantially perpendicular to said longitudinal axis, the half-clamps orientated in substantially the same direction whereupon attaching each half-clamp to a substantially vertical scaffold tube causes the support member to be substantially horizontal.
 6. A scaffold system, comprising: a plurality of substantially vertical scaffold tubes positioned in a spaced apart configuration; and a plurality of substantially horizontal support members releasably connected to each pair of adjacent vertical scaffold tubes, each support member comprising a rigid bar having first and second ends and defining a longitudinal axis, the bar having a half-clamp at each of the first and second ends, each half-clamp oriented to clamp a tube whose axis is substantially perpendicular to said longitudinal axis, the half-clamps oriented in substantially the same direction whereupon attaching each half-clamp of a support member to a substantially vertical scaffold tube causes the support member to be substantially horizontal.
 7. The scaffold system as forth in claim 6 wherein the bar is a metal scaffold tube.
 8. The scaffold system as set forth in claim 6 wherein the half-clamps are welded to the bar.
 9. The scaffold system as set forth in claim 6 wherein each half-clamp is a releasable clamshell clamp.
 10. The scaffold system as set forth in claim 6 further comprising: (a) at least one pair of brace clamps, each brace clamp consisting of a half-clamp having a base and fastening means for releasably attaching a scaffold brace to the brace clamp, the fastening means projecting substantially perpendicular from the base whereupon the brace clamp being fastened to a scaffold tube having a longitudinal axis, the fastening means is substantially perpendicular to the longitudinal axis; (b) each of said pair of brace clamps attached to one of a pair of adjacent vertical tubes; and (c) the scaffold brace having first and second ends, each end having an aperture for receiving the fastening means, each end of the brace releasably attached to one of said pair of brace clamps.
 11. A brace clamp for a scaffold brace having first and second ends, each end having an aperture for receiving a fastener, comprising: a half-clamp having a base; and a fastener for releasably attaching the scaffold brace to the brace clamp, the fastener projecting substantially perpendicular from the base of the brace clamp whereupon the brace clamp being attached to a scaffold tube having a longitudinal axis, the fastener extends substantially perpendicular to the longitudinal axis for attaching to an aperture of the scaffold brace.
 12. The brace clamp as set forth in claim 11 wherein the fastener is a bolt and a nut whereby the bolt extends through an aperture of the scaffold brace and the nut is then threaded onto the bolt to secure the scaffold brace to the brace clamp.
 13. The brace clamp as set forth in claim 11 wherein the fastener is a quick release scaffold brace attachment mechanism that extends through an aperture of the scaffold brace to secure the scaffold brace to the brace clamp. 